Search results for "sequence"
showing 10 items of 4987 documents
Una storia italiana: Giorgio e Isabella
2018
Si tratta, qui, della storia di due italiani dalla “pelle scura” raccontata, per Giorgio Marincola, da Carlo Costa e Lorenzo Teodonio in Razza partigiana e, per la sorella Isabella, da Wu Ming 2 e Antar Mohamed in Timira. Romanzo meticcio. Le loro vicende, così come molti altri aspetti della nostra storia coloniale, neocoloniale e postcoloniale, sono riemerse dal buio nel quale erano state occultate solo nell’ultimo quindicennio, grazie alla riapertura degli archivi che ha permesso di ridiscutere molti degli aspetti che nelle pagine di Storia, così come in quelle letterarie, erano stati raccontati in altro modo. I due testi, che hanno inevitabilmente finito per incontrarsi e che potremmo in…
Biomimetic synthesis of the tumor-associated (2,3)-sialyl-T antigen and its incorporation into glycopeptide antigens from the mucins MUC1 and MUC4.
2004
Glycoproteins on epithelial tumor cells often exhibit aberrant glycosylation profiles. The incomplete formation of the glycan side chains resulting from a down-regulated glucosamine transfer and a premature sialylation results in additional peptide epitopes, which become accessible to the immune system in mucin-type glycoproteins. These cancer-specific structure alterations are considered to be a promising basis for selective immunological attack on tumor cells. Among the tumor-associated saccharide antigens, the (2,3)-sialyl-T antigen has been identified as the most abundant glycan, found in several different carcinoma cell lines. According to a linear biomimetic strategy, the (2,3)-sialyl…
Glucosylation of Rho proteins by Clostridium difficile toxin B.
1995
TOXIN A and B, the major virulence factors of Clostridium difficile, are the causative agents of antibiotic-associated pseudomembran-ous colitis. In cultured cell lines their potent cytotoxicity results from their ability to induce disaggregation of the microfilament cytoskeleton1,2. Toxin B acts on the low-molecular-mass GTPase Rho A3,4, which is involved in the regulation of the actin cytoskeleton. We report here that toxin B catalyses the incorporation of up to one mole of glucose per mole of RhoA at the amino acid thre-onine at position 37. The modification was identified and localized by tandem electrospray mass spectrometry. UDP-glucose selectively serves as cosubstrate for the monogl…
Bradykinin-induced Internalization of the Human B2Receptor Requires Phosphorylation of Three Serine and Two Threonine Residues at Its Carboxyl Tail
1999
The binding of bradykinin (BK) to B2 receptor triggers the internalization of the agonist-receptor complex. To investigate the mechanisms and the receptor structures involved in this fundamental process of receptor regulation, the human B2 receptor was mutated within its cytoplasmic tail by complementary strategies of truncation, deletion, and amino acid substitution. Ligand binding, signal transduction, internalization as well as phosphorylation were studied for the mutated receptors expressed in COS, CHO, and HEK 293 cells. Truncation of 44 out of 55 amino acid residues of the receptor's cytoplasmic tail corresponding to positions 321-364 did not alter the kinetics of BK binding and the r…
JNK phosphorylation relieves HDAC3-dependent suppression of the transcriptional activity of c-Jun
2003
The AP-1 transcription factor c-Jun is a prototypical nuclear effector of the JNK signal transduction pathway. The integrity of JNK phosphorylation sites at serines 63/73 and at threonines 91/93 in c-Jun is essential for signal-dependent target gene activation. We show that c-Jun phosphorylation mediates dissociation of an inhibitory complex, which is associated with histone deacetylase 3 (HDAC3). The subsequent events that ultimately cause increased mRNA synthesis are independent of c-Jun phosphorylation and its interaction with JNK. These findings provide an 'activation by de-repression' model as an explanation for the stimulatory function of JNK on c-Jun.
Ras, Rap, and Rac Small GTP-binding Proteins Are Targets for Clostridium sordellii Lethal Toxin Glucosylation
1996
Lethal toxin (LT) from Clostridium sordellii is one of the high molecular mass clostridial cytotoxins. On cultured cells, it causes a rounding of cell bodies and a disruption of actin stress fibers. We demonstrate that LT is a glucosyltransferase that uses UDP-Glc as a cofactor to covalently modify 21-kDa proteins both in vitro and in vivo. LT glucosylates Ras, Rap, and Rac. In Ras, threonine at position 35 was identified as the target amino acid glucosylated by LT. Other related members of the Ras GTPase superfamily, including RhoA, Cdc42, and Rab6, were not modified by LT. Incubation of serum-starved Swiss 3T3 cells with LT prevents the epidermal growth factor-induced phosphorylation of m…
Stressing Sequence for Hanger Replacement of Tied-Arch Bridges with Rigid Bars
2022
The construction of bridges with suspenders, such as cable-stayed or tied-arch bridges, needs deep study of the prestressing forces to be applied to stays or hangers in all stages, depending on the construction technique adopted. In these cases, the main issue is the determination of the initial forces and optimization of the prestressing system in terms of stressing values and sequence. When the bridge is already built and suspenders have to be replaced for maintenance, a different problem has to be faced by the engineer, because the sequence of replacements and the values of the axial stresses depend very much on the service conditions of the bridge and on its historical evolution from co…
Long-term tillage and crop sequence effects on wheat grain yield and quality.
2013
Much research around the world has compared the performance of cereals grown under conventional and conservation tillage systems; however, relatively few long-term experiments have been conducted in Mediterranean areas, and little attention has been given to interactions among tillage techniques and other system components across space and time. In this study, we investigated the effects of the long-term (18-yr) use of three tillage techniques (conventional tillage, CT; reduced tillage, RT; and no-till, NT) on wheat (Triticum durum Desf.) grain yield and quality within three crop sequences: continuous wheat, faba bean (Vicia faba L.)–wheat, and berseem clover (Trifolium alexandrinum L.)–whe…
Unveiling distribution patterns of freshwater phytoplankton by a next generation sequencing based approach.
2012
The recognition and discrimination of phytoplankton species is one of the foundations of freshwater biodiversity research and environmental monitoring. This step is frequently a bottleneck in the analytical chain from sampling to data analysis and subsequent environmental status evaluation. Here we present phytoplankton diversity data from 49 lakes including three seasonal surveys assessed by next generation sequencing (NGS) of 16S ribosomal RNA chloroplast and cyanobacterial gene amplicons and also compare part of these datasets with identification based on morphology. Direct comparison of NGS to microscopic data from three time-series showed that NGS was able to capture the seasonality in…
A novel and rapid prediction assay for the effectiveness of IL-6 receptor specific antisense oligonucleotides by proliferation inhibition of an inter…
2001
Interleukin-6 (IL-6) belongs to a family of cytokines that use receptors consisting of a common signal-transducing chain (gp130). Baf/3 cells transfected with the human IL-6 receptor (IL-6R) and gp130 (Baf/3-gp130/IL-6R) can only grow in medium containing IL-6. We attempted to interrupt the signal transducing pathway of IL-6 with the help of antisense oligonucleotides (ASOs) designed against the IL-6R. We used 18 different kinds of antisense oligonucleotides of overlapping sequences around the translational start codon of the human IL-6R. Sense ASOs were used as a control. The proliferation of cells was analysed by H-thymidine incorporation. Cell surface expression of the IL-6R was assessed…